Cardinali D P, Fernández Pardal J, Gimeno M F, Gimeno A L
J Neural Transm. 1982;53(1):39-47. doi: 10.1007/BF01243518.
The spontaneous and K+-stimulated efflux of norepinephrine (NE) and the release of PGE2 and PGF2 alpha were examined in medial basal hypothalamus (MBH) of ovariectomized rats killed before and during the LH release that follows estradiol treatment. As compared to vehicle-treated, ovariectomized rats, estradiol-primed rats exhibited a 60% more increase in K+-stimulated 3H-overflow of MBH slices preloaded with 3H-NE at morning hours (1000 hours). Estradiol treatment did not result in further increase of K+-induced 3H release from MBH slices at the time of LH release (1700 hours), nor affected labeled NE release in occipital cortex slices. A significant difference between K+-stimulated NE release of vehicle-treated spayed rats killed at 1000 and 1700 hours was observed, the latter showing 54% more release upon stimulus. PGE2 efflux was time-dependent being highest at the evening in both vehicle- and estradiol-treated animals. The MBH of estrogenized rats released significantly more PGE2 at the evening as compared to the controls. The release of PGF2 alpha remained essentially unchanged regardless of estradiol treatment or time of day. The present results offer additional support to the involvement of MBH catecholamines and prostaglandins in the mechanism of LH secretion in the rat.
在雌二醇处理后促黄体生成素（LH）释放之前及期间处死的去卵巢大鼠的内侧基底下丘脑（MBH）中，检测了去甲肾上腺素（NE）的自发和K⁺刺激外流以及前列腺素E2（PGE2）和前列腺素F2α（PGF2α）的释放。与接受载体处理的去卵巢大鼠相比，在上午（1000时），用雌二醇预处理的大鼠中预先加载3H-NE的MBH切片的K⁺刺激的3H溢出增加了60%。在LH释放时（1700时），雌二醇处理并未导致MBH切片中K⁺诱导的3H释放进一步增加，也未影响枕叶皮质切片中标记NE的释放。观察到在1000时和1700时处死的接受载体处理的去势大鼠的K⁺刺激的NE释放之间存在显著差异，后者在刺激时释放增加了54%。PGE2外流呈时间依赖性，在接受载体处理和雌二醇处理的动物中，晚上时最高。与对照组相比，雌激素处理的大鼠的MBH在晚上释放的PGE2明显更多。无论雌二醇处理或一天中的时间如何，PGF2α的释放基本保持不变。目前的结果为MBH儿茶酚胺和前列腺素参与大鼠LH分泌机制提供了更多支持。
